<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title></title>
</head>
<body>
这是登录后的跳转界面
<%
    String username = request.getParameter("username");
    session.setAttribute("username",username);
    int number = 0;
    if (application.getAttribute("userNumber")!=null){
        number=(Integer)application.getAttribute("userNumber");
    }
    number++;
    application.setAttribute("userNumber",number);
%>
当前登录用户数量：
<%=application.getAttribute("userNumber")%>
</body>
</html>